yaffs_packedtags1.c

   1 /*
   2  * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
   3  *
   4  * Copyright (C) 2002-2018 Aleph One Ltd.
   5  *
   6  * Created by Charles Manning <charles@aleph1.co.uk>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include "yaffs_packedtags1.h"
  14 #include "yportenv.h"
  15
  16 static const u8 all_ff[20] = {
  17         0xff, 0xff, 0xff, 0xff,
  18         0xff, 0xff, 0xff, 0xff,
  19         0xff, 0xff, 0xff, 0xff,
  20         0xff, 0xff, 0xff, 0xff,
  21         0xff, 0xff, 0xff, 0xff
  22 };
  23
  24 void yaffs_pack_tags1(struct yaffs_packed_tags1 *pt,
  25                       const struct yaffs_ext_tags *t)
  26 {
  27         pt->chunk_id = t->chunk_id;
  28         pt->serial_number = t->serial_number;
  29         pt->n_bytes = t->n_bytes;
  30         pt->obj_id = t->obj_id;
  31         pt->ecc = 0;
  32         pt->deleted = (t->is_deleted) ? 0 : 1;
  33         pt->unused_stuff = 0;
  34         pt->should_be_ff = 0xffffffff;
  35 }
  36
  37 void yaffs_unpack_tags1(struct yaffs_ext_tags *t,
  38                         const struct yaffs_packed_tags1 *pt)
  39 {
  40         if (memcmp(all_ff, pt, sizeof(struct yaffs_packed_tags1))) {
  41                 t->block_bad = 0;
  42                 if (pt->should_be_ff != 0xffffffff)
  43                         t->block_bad = 1;
  44                 t->chunk_used = 1;
  45                 t->obj_id = pt->obj_id;
  46                 t->chunk_id = pt->chunk_id;
  47                 t->n_bytes = pt->n_bytes;
  48                 t->ecc_result = YAFFS_ECC_RESULT_NO_ERROR;
  49                 t->is_deleted = (pt->deleted) ? 0 : 1;
  50                 t->serial_number = pt->serial_number;
  51         } else {
  52                 memset(t, 0, sizeof(struct yaffs_ext_tags));
  53         }
  54 }